A graphical representation showing the refractive index of the core and cladding of a fiber. For a step-index fiber, the graph will show a stair-step-type pattern with the top step at the core of the fiber. For a graded-index fiber, the graph will show a parabolic curve with its peak at the core of the fiber.

A graphical representation showing the refractive index of the core and cladding of a fiber. For a step-index fiber, the graph will show a stair-step-type pattern with the top step at the core of the fiber. For a graded-index fiber, the graph will show a parabolic curve with its peak at the core of the fiber.